The purpose of this Core is to provide a state-of-the-art NMR facility and medicinal chemistry expertise for the research in this program project grant. Both aspects are linked with each other and to the research components ofthe grant. The personnel will be responsible for keeping the NMR Facility and its instruments accessible, in optimal conditions, updated, and running without interruptions. The personnel will assure that existing and newly developed experimental techniques are made fully available to all participants and outside investigators on a 24-hour basis, 365 days of the year. This requires a very significant effort given the complexity and variation ofthe facility's instrumentation, and will be achieved through a close interaction between the director of the NMR facility, Gregory Heffron, and the PI, Gerhard Wagner via frequent meetings to discuss strategies for effective and economical operation ofthe lab which houses three 500's, two 600's, one 750, one 800, and the solution part of a 900 MHz instrument. In the coming months, a new Agilent 700MHz system with a high-sensitivity cryogenic probe will be installed and made available to the participants. Thus, the core is of central importance to this program project grant, and has demonstrated the ability to operate a highly productive NMR center with minimal downtime for nearly 20 years. In addition to supporting the NMR facility the Core will support specific research objectives in this grant by supporting high-throughput screening of ICCB compound libraries, NMR-based fragment screening and measuring inter-ligand NOEs of fragments, and the chemistry effort required to link fragments and optimize HTS hits or tethered compounds. In particular, these functions within the core will support discovery and optimization of inhibitors of the bacterial non-ribosomal peptide synthetase (Enterobactin Synthetase, Component 2),the TCR signaling component (Component 3), and the pleiotropic drug resistance mechanism of pathogenic yeasts (Component 4). Dr. Nathanael Gray at Dana Farber Cancer Institute, a world expert in discovery and optimization of kinase inhibitors and other drugs, will direct the medicinal chemistry effort on these projects. Nathanael Gray and his group routinely work with investigators at Dana-Farber Cancer Institute on all aspects of small molecule probe and drug discovery from hit identification following high throughput screening to developing advanced molecules highly optimized for potency, physical properties, in vitro DMPK, and in vivo PK.